Exhaust head assembly



2 sheets-sheet 1 Filed Nov. 29, 1951 m MK m m MM D 0 HM W w.

INVENTORS 44 Aw B M L). Elm

ATTORNEYS FIG. 2

May 18, 1954 H. G. WARREN ET AL EXHAUST HEAD ASSEMBLY 2 Sheets-Sheet 2 Filed Nov. 29, 1951 HORACE a. WARREN .1000 H. BLACK INVENTORS MjQJM ATTORNEYS Patented May 18, 1954 UNITED STATES TENT OFFIE N. Y., Consolidated assignors, by mesne assignments, to

Vacuum Corporation,

Rochester,

N. Y., a corporation of New York Application November 29, 1951, Serial No. 258,772 17 Claims. (01. 226-201) This invention relates to apparatus for use in evacuating articles such as radio tubes or the like and is particularly concerned with a combined exhaust port and vacuum valve assembly forming an exhaust head assembly especially adapted for use in tube evacuating equipment.

The manufacture of many hollow articles involves evacuation at some stage of the process. Thus in the case of the so-called vacuum tubes such as radio tubes, cathode ray tubes, X-ray tubes and the like, the tubes are evacuated, and then sealed off while so evacuated. In other cases, articles such as light bulbs and liquid switches are evacuated and back filled with a different gas or liquid.

Vacuum tubes and similar articles are usually evacuated by means of a pumping system comprising a high vacuum diffusion pump backed by a mechanical vacuum pump. Exhausting apparatus to be commercially successful must be capable of a very high production rate; since, for example, miniature vacuum tubes are usually processed at the rate of at least 800 tubes per hour on a single exhausting machine with a plurality of exhaust ports.

Exhausting apparatus must include a suitable exhaust port for connecting the article to be evacuated to the pumping system, and a suitable vacuum valve assembly for opening the vacuum system after the article to be evacuated is sealed into the exhaust port and for closing the vacuum system before the finished article is removed from the port. Prior to this invention, solenoid valves were commonly employed for opening and closing the vacuum system, either in response to pressure changes or by means of electrical contacts operable at predetermined positions or at predetermined times. Such solenoid valves had the disadvantages of being subject to mechanical failure and of necessitating an expensive and complex system.

Various types of exhaust ports were used prior to this invention. In some cases, the neck of a glass article was fused to a glass conduit at the port, this necessarily being a cumbersome and expensive method. In other cases, the neck of the article was forced through an opening in a rubber gland. lhis necessitated either polishing the neck of the article to prevent cutting of the gland or frequent changing of the gland. Furthermore, insertion and removal of tubes or similar, article was a slow and diflicult process. With glass tubes, this method frequently led to breakage of the neck in the gland with consequent added effort to remove the neck before insertion of the next tube.

It is accordingly anobject of this invention to provide a new and improved exhaust head assembly comprising a combined exhaust port and vacuum valve assembly.

Another object of the invention is to provide an exhaust port can be inserted and removed without the difliculties attendant to usual ports.

Another object of the invention is to provide simple valve means minimizing chanical failure and ensuring closing of the system during insertion and removal of the articles to be evacuated and opening of the system in response to scaling the article into the exhaust port.

Another object of the invention is to provide a simplified assembly which functions mechanically both as an exhaust port and a vacuum valve.

Another object of the invention is to provide a combined port and valve assembly wherein the action of the valving system isv automatically and mechanically responsive to the action of the exhaust port.

Another object of the invention is to provide an exhaust port including simple and efiective means for back filling evacuated articles.

Another object of the invention is to provide a port and valve assembly wherein the port mechanism and the valve mechanism coact mechanically to ensure proper synchronization of their respective functions.

Another object of the invention is to provide a combined port and valve assembly having a minimum volume to be exhausted in each evacuating cycle.

Another object of the invention is toimprove apparatus especially adapted for facilitating high speed processing of vacuum tubes.

Another object of the invention is to provide a simple and compact port and valve exhaust head assembly adapted to be mounted directly on a high Nacuum diffusion pump.

Another object of the invention is to provide a port and valve assembly of a construction particularly effective for minimizing mechanical failure.

Other objects will be apparent from the drawings and from the description and claims which follow.

These and other objects of the invention are attained by the apparatus embodying this in-. vention asdescribed more fully hereinafter with wherein articles to be evacuated the risk of me-.

3 reference to the preferred embodiment illustrated in the drawings.

Of the drawings:

Fig. 1 is a top view, partially broken away and in section, of a preferred port and valve assembly combining to form an exhaust head assembly embodying the invention, the assembly being shown with the port open and the valve closed;

Fig. 2 is a View in elevation, partially broken away and in section, of the preferred apparatus shown in Fig. 1;

Fig. 3 is a top view partially broken away and in section of the apparatus of Fig. 1, shown with the port closed and the valve open;

Fig. 4 is a fragmentary sectional view in elevation of the preferred apparatus shown with the port closed and the valve open;

Fig. 5 is a view in elevation, partially broken away and in section of an alternative port and valve assembly embodying the invention;

Fig. 6 is a top view, partially broken away and in section, of the apparatus shown in Fig. 5; and

Fig. 7 is a fragmentary view in elevation of the toothed upper rim of the assembly housing.

In apparatus embodying this invention, a housing and a closure assembly combine to form an evacuable chamber. The closure assembly is provided with an opening extending therethrough communicating with the chamber and adapted to receive the neck of an article to be evacuated. The housing includes at least one exhaust outlet for evacuating the chamber when connected with a suitable pumping system. Inside the chamber is a stationary valve member which is arranged for closing the opening in the closure assembly. An extensible bellows member is disposed in the chamber so as to encircle the valve member, one end of the bellows member being secured to the closure assembly around the opening through the closure assembly, the other end of the bellows member being secured to the housing around the exhaust outlet.

The closure assembly includes a resilient sealing member having the opening extending through it, together with adjustable means for alternately compressing and releasing the sealing member. The apparatus also includes means cooperating mechanically with the adjustable means for moving the closure assembly out of closing relation with the stationary valve member during compressing of the sealing member whereby both the opening through the closure assembly and the exhaust outlet are in communication with the chamber when the sealing member is compressed in vacuum tight relation around the neck of the article to be evacuated, the apparatus being constructed and arranged for maintaining the valve member in closing relation with the closure assembly when the sealing member is uncompressed.

Thus, in operation, the neck or similar portion of an article to be evacuated is inserted into the opening through the closure assembly which serves as a port, the opening being sealed off from the chamber by the valve member. The resilient sealing member is then compressed inwardly against the neck of the article to be evacuated thus closing the port and forming a vacuum-tight seal. The movement of the adjustable means which compresses the sealing member also causes the closure assembly to move out of closing relation with the valve whereby the closure assembly opening and hence the article to be evacuated is in direct communication with the chamber and, through the chamber and exhaust outlet, with the vacuum pumping system. The bellows member effectively maintains the vacuum during movement of the closure assembly out of closing relation with the valve member. The apparatus is maintained in this position until the article is evacuated and sealed, whereupon the sealing member is released and returned to the uncompressed position, the closure assembly moves back into closing relation with the valve member and the evacuated article is removed from the apparatus without opening the pumping system to the atmosphere.

With reference to the drawings illustrating a preferred embodiment of the invention and with particular reference to Fig. 2, the combined port and valve assembly comprises a cylindrical metal housing It and a closure assembly I I which combins to define an evacuable chamber I 2. Closure assembly II is provided with a port opening I3 extending therethrough and communicating with chamber I2, port opening I3 being adapted to receive the neck of an article I5 to be evacuated. A stationary valve rod I4 is mounted on housing I 8 inside chamber I2 and extends into closing relation with port opening I3 in closure assembly II. Housing I0 includes at least one exhaust outlet I6 communicating with chamber I2 for evacuating the chamber, housing I!) being adapted to be connected to a vacuum pumping system and preferably being mounted directly on the inlet end of a diffusion pump I! as shown in Fig. 2. A longitudinally extensible bellows I8 is disposed in chamber I2 and encircle valve member I l. One end of bellows I8 is welded or otherwise secured in vacuum-tight relation to closure assembly H around opening IS. The other end of bellows member I8 is similarly secured in vacuum-tight relation to housing I 0 around valve 1'; member i4 and exhaust outlet I6.

Housing I0 preferably comprises a generally tubular side wall 20 and a base plate 2I marginally bolted or otherwise secured together to form a cylindrical housing having an open end. The upper rim of side wall 20 has a plurality of raised portions 22, 22 regularly spaced around the circumference of wall 20 to give the housing ID a toothed marginal profile, each of the raised portions comprising inclined terminal faces 23, 23 slanting upwardly to a generally flat central zone 24 having a lateral groove 25 across its face as illustrated more clearly in Fig. 7.

Closure assembly II comprises a metal plate 21 journalled in housing I 0 adjacent the open end thereof, a second plate 28 spaced from the first plate 2'1 and rigidly secured thereto by stud bolt 29, a resilient sealing member 30 of rubber or other suitable resilient material sandwiched be-- tween plates 21 and 28 and adjustable means for compressing sealing member 30. Opening I3 extends through plates 21 and 28 and sealing member 30. A ring 3| is sandwiched between plates 21 and 28 and encircles sealing member 30, ring 3| being free to rotate about sealing member 30. The inner face 32 of ring 3| has a sinuous configuration forming a plurality of regularly recurring recesses around the inner circumference of ring 3! with the radial spacing of the recesses corresponding to the spacing of the raised portions 22, 22 on housing I 0.

A plurality of incompressible balls such as steel balls 38, 33 are disposed between ring 3| and sealing member 38 in radial alignment with the raised portions 22, 22 on housing I 0. Plate 21 has an upstanding annular rib 34 which abuts 3| are correlated so thatthe balls exert no sub-- stantial pressure on sea-ling member 30 when seated in. such recesses.

A plurality of rollers 35, 35 corresponding in number tothe number of raised portions 22, 22 on housing ware rotatably mounted on stud bolts 33,

36 secured to and projecting outwardly from the outer face 31-01? ring 3| at spaced-apart intervalsaround the circumference of ring 3 Rollers 35. 35roll on the toothed rim face of housing l9, and are positionedcircumferentially on radii bisecting the inner face 32 of ring 3| between the recessed portions of the inner face. Member 38 projecting outwardly from one of the rollers 35'forms a bandle for rotating ring 3|.

Collar 40 mountedon the inner face of" the end wall 2| of housing i and extending upwardly be tween bellows member is andsidewall 2.0 limits downward movement of closure assembly i into housing I0. Removable pin 3| projecting outwardly fromplate member 21 into opening 42 in side wall of housing It limits lateral and vertical movement of closure assembly H to a predetermined zone.

In a preferred embodiment, valve rod It is bored axially to provide at least one back fill conduit 43 through rod 24, the conduit 43 communicating with a conduit 44 bored in base plate 2| of housing It. A suitable conduit tube at is secured to housing l!) in communication with conduits 43 and M for connection with a reservoirof back filling fluid (not shown), tube it being provided with a suitable valve 11.

In operating the apparatus embodying the invention as illustrated in Fig. 2, the combined port and valve assembly is connected to a suitable vacuum pumping system. In the case of cathode ray tubes and the like wherein a high vacuum must be attained, the pumping system usually comprises at least one diffusion pump backed by a mechanical pump. In the embodiment illustrated in Fig. 2, the combined assembly is attached directly to the intake end of a diffusion pump with the exhaust outlet of the combined valve and port assembly communicating directly with the pumping chamber. This direct connection is made possible because of the small air capacity of the port and valve assembly whereby pumping directly into a hot diffusion pump can be successfully effected.

With the port in the open position as shown in Figs. 1 and 2, the-pumping system can be started immediately and kept in operation continuously. When the port is open, valve rod M seats in opening l3 in sealing member and effectively seals the port. The pumping system evacuates the interior of bellows |8 which further serves to hold the closure assembly in tightly closed relation with valve rod I l.

The neck of an article |5 to be evacuated is inserted in opening It so as to extend through sealing member 30 and rest on valve rod M. Ring 31 is then turned through a part of a revolution, either manually or by any suitable mechanism, whereby each of the rollers 35, ride up an inclined face 23 of a raised portion 22 on the rim of. housing l0 and seats in the groove 25 on the flat top 24 of the raised portion. This practices, and the movement of the rollers up. onto theraised por tions serves to raise the entire closure assemblyout of closing relation with valve member I4.

The-rotation of ring 3| simultaneously effectscompression of sealing member 30 into vacuumtight relation with the neck of article I5 since balls 33, 33 are forced inwardly by the ring as they move out of the recesses in the inner face-32 of ring 3|, the balls being confined in rib 34 on plate 2'! to prevent movement except radially of the closure assembly. The relative positions ofthe balls 33, 33, and rollers 35, 35 with the port closed and the valve open is illustrated by Figs; 3 and 4 of the drawings. It is thus apparent that the closing of the port and valve are correlated mechanically two operations necessarily occur simultaneously and positively without the necessity of employing external controlling means.

The apparatus embodying the invention is maintained in the position shown in Figs. 3 and 4- until the article being treated has been evacuated to the desired reduced pressure. The article is then tipped off in accordance with conventional ring 3i rotated until rollers 35, 35 are again on housing iii, during which movement the entire closure assembly is pulled downwardly bythe vacuum until valve rod I l seats in opening I3 and the balls 33, 31% move into the recesses on the inner face of ring 3| and relieve the compression on sealing member 3; Sealing member 3%, being resilient, resumes its normally uncompressed position as shown in Fig. 2, thus releasing the neck of article It which can thereupon be removed and the cycle repeated with another tube or similar article.

In some cases, as in the processing of electric lig t bulbs, it is desirable to evacuate the bulb and then back fill it with another gas such as nitrogen or the like. In such case, the dimensions of the various elements of the apparatus embodying the invention are correlated so that, during the movement of the ring from the closed to the open position, the closure assembly drops. down and seats on valve rod Hi before the compression force on sealing member 38' is fully released. At this point, valve i? is opened and back filling fluid enters the evacuated article through back fill conduit t3 in valve rod l4.

An alternate embodiment of the invention parcularly adapted for use on automatic exhausting equipment, such as a multiple head rotary exhaust apparatus, is illustrated in Figs. 5 and 6. In this embodiment ring 3| is bored at predetermined intervals to provide holes 50, 53 through.

ring 3| of slightly smaller diameter than balls 33, 33. Holes 50, to form recessed seats adapted to receive balls 33, 33 at predetermined zones along the path of rotation of ring 3|.

52 which ensures optimum sealing with member sealing member- 39" and alsopermits the use ofthe opening of the whereby the the lower zones of the rim of By the use of bored holes as ball seats instead of recesses 30 with various sized openings without necessitating the use of a diiferent valve rod. Collar 40 is welded or otherwise secured to plate 21 and is unsecured to base plate 2| in this alternative embodiment. Collar 4'0 is dimensioned to make sliding contact with the inner wall of housing It] over a larger area than with only plate 21 journalled in housing I0. This imparts additional stability to the assembly during operation and collar 40 still functions to limit downward movement of the closure assembly to a predetermined point.

The apparatus illustrated in Figs. 5 and 6 operates in substantially the same way as the apparatus shown in Fig. 1 except that compression and decompression of sealing member 36 by balls 33, 33 takes place during a shorter arc of rotation of ring 3|. Members 5!, 5i successively move into position to engage automatic external actuating means during rotation of ring 30 whereas, in manual operation, only a single handle 38 is necessary as shown in Fig. 2.

The assembly embodying the invention can be employed as an individual tube evacuating unit or it can be incorporated in multiple-head processing equipment as described particularly with reference to Figs. 5 and 6. In the latter case, the assembly is desirably actuated mechanically and automatically at predetermined zones or stations during the processing cycle.

The invention thus provides a simple, positiveacting assembly combining the functions of an exhausting port and a vacuum valve cooperating mechanically. The assembly is adapted for rapid loading and unloading of articles being treated, and ensures sealing of the article in the port during evacuation. The various elements of the assembly are mechanically correlated to obviate the possibility of opening the pumping system to the atmosphere and permits continuous operation of the vacuum pumping system.

While the invention has been described in considerable detail with reference to a preferred embodiment thereof, it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described hereinabove and illustrated in the drawings and as defined in the appended claims.

We claim:

1. A combined port and valve assembly forming an exhaust head assembly comprising housing means and closure means defining an evacuable chamber, said closure means having an opening therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing means including an exhaust outlet for evacuating said chamber, a stationary valve member mounted in said chamber and being arranged for closing said opening in said closure means, extensible bellows means in said chamber and encircling said valve member, one end of said bellows means being secured to said closure means around said opening, the other end of said bellows means being secured to said housing means around said exhaust outlet, said closure means comprising resilient sealing means having said opening extending therethrough, and adjustable means for alternately compressing and releasing said sealing means, and means cooperating with said adjustable means and arranged for moving said closure means out of closing relation with said stationary valve member during compression of said sealing means whereby both said opening and said exhaust outlet are in communication with said chamber when said sealing means is compressed, said closure means being free to move into closing relation with said valve member when said sealing means is uncompressed.

2. An exhaust head assembly comprising housing means and closure means defining an evacuable chamber, said closure means having an opening therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing means including at last one exhaust outlet for evacuating said chamber, a stationary valve member mounted on said housing means in said chamber and arranged for closing said opening in said closure means, and extensible bellows means disposed in said chamber and encircling said valve member, one end of said bellows means being secured to said closure means around said opening, the other end of said bellows means being secured to said housing means around said exhaust outlet and said valve member, said closure means comprising resilient sealing means having said opening extending therethrough, and adjustable means for alternately compressing and releasing said sealing means, said housing means including means cooperating with said adjustable means and arranged for raising said closure means out of closing relation with said valve member during compression of said sealing means, said closure means being movable into closing relation with said valve member when said sealing means is uncompressed.

3. An exhaust head assembly comprising housing means and closure means defining an evacuable chamber, said closure means having an opening therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing means including at least one exhaust outlet for evacuating said chamber, a stationary valve member mounted on said housing means in said chamber and arranged for closing said opening in said closure means, and extensible bellows means disposed in said chamber and encircling said valve member, one nd of said bellows means being secured to said closure means around said opening, the other end of said bellows means being secured to said housing means around said exhaust outlet and said valve member, said closure means comprising resilient sealing means having said opening extending therethrough and adjustable means encircling said sealing means and mounted for rotation around said sealing means, said adjustable means including means for alternately compressing and releasing said sealing means during rotation of said adjustable means, and means cooperating with said adjustable means for raising said closure means out of sealing relation with said valve member, said means for raising said closure means being constructed and arranged to coact with said adjustable means to raise said closure means during the portion of rotation of said adjustable means in which said means for compressing said sealing means is operable, said means for raising said closure means being inoperative during the remainder of the rotation of said adjustable means.

4. An exhaust head assembly comprising housing means and closure means defining an evacuable chamber, said closure means having an opening therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing means including at least one exhaust outlet for evacuating said chamber, a stationary valve member haust outlet and said valve member,

mounted on: said housing means in said chamber and arranged for closing said opening in said closure means, and extensible bellows means disposed in said chamber and encirclin said valve member, one end of said bellows means being secured to said closure means around said opening, the other end or said bellows means being secured to said housing means around said exsaid closure means comprising resilient sealing means having said opening extending therethrough and adjustable means encircling said sealing means and mounted for rotation around. said sealing means, said adjustable means including means for alternately compressing and releasing said sealing means in predetermined zones along the path of rotation of said adjustable means, said housing means including means: for raising said closure means out of sealing relation with said valve member, said means for raising said closure means comprising spaced apart raised portions on said housing means adjacent said closure means; said raised portions being at predetermined intervals along said housing means in radial alignment with said zones along the path of rotation of said adjustable member wherein said means for compressing said sealing means are operable, said adjustable means including means arranged in cooperating relation with said raised portions of saidhousing means and being constructedzto raise said closure means during passageoversaid raised portions.

5.. An exhaust head assembly comprising housing means having an open end, closure means for the. open end of said housing means, said housing means and'said closure means forming anevacuable chamber, said closure means havingan' opening therethrough communicating with said chamber and'being adaptedto receive the neckof an article-to be evacuated, said housing-means including at least one exhaust outlet' for'evacuatingsaid chamber, a stationary valve member mounted" in said chamber and arranged to close-the openingin said closure means, extensible bellows means-disposed in saidchamher, andencircling saidivalvemember, one end of said bellows means being secured to said closuremeans around said opening, theother end of said bellows means being secured to said housing around means comprising resilient sealing I means hav in said opening extending therethrough and adjustablemeans encircling: said sealing means and mounted for rotation aroundsaid sealing means, said adjustable means including means for alternately compressing and releasing said sealing means in predetermined :zones alongthe path of rotation of said adjustable means, the rim of said housing at the open end of said housing means adjacent said closure means being formed withv a. plurality of spaced apart raised portions around said rim in radial alignment with said predetermined. zones, said adjustable means includingroller means riding on said rim of saidhousing means and arranged to raise said closure means during passage over said raised portions.-

6. An exhaust head assembly housingmeans and closure means defining an evacuable chamber, said. closure means having with an opening therethrough communicating said chamber and being adapted toreceive the neck of an article to be evacuated, said housing meansincluding at least one exhaust outlet for evacuating; said chamber, a stationary valve said exhaust outlet, said closure comprising rod mounted on said housing means in said chamber and arranged to close said opening in said closure means, extensible bellows means disposed in said chamber and encircling said valve rod, one end of said bellows means being secured to said closure means around said openmg, the other end of said bellows means being secured to said housing means around said exhaust outlet and said valve rod, said closure means being unsecured to said housing means and movable relative to said housing means, said closure means comprising resilient sealing means having said opening extending therethrough in alignment with said valve rod, and adjustable means encirc s said sealing means and rotatable about said sealing means, said adjustable means includ means for alternately compressing and releasing said sealing means in predetermined zones along the path of rotation of said adjustable means, said housing means including adjacent to said closure means arranged in cooperating relation with said adjustable means for raising said closure means out of sealing relation with said valve rod in said predetermined zones along the path of'rotation of said adjustable means.

'7. An exhaust head assembly comprising housing means and closure means defining an evacuable chamber, said closure means having an opening therethrough communicating with said. chamber and being adapted to receive the neck of article to be evacuated, said housing means including at least one exhaust outlet for evacuating said chamber, a stationary valve member mounted in said chamber and arranged for closing said opening in said closure means, and extensible bellows means-disposed in said chamber encircling said valve member, one end of said bellows means being secured to said closure means around said opening, the other end of said bellows means being secured to said housing means around said exhaust outlet, said closure means comprising resilient sealing means having said opening' extending therethrough, ring means encircling said sealing means and rotatable about said sealing means, pressuretransmitting means positioned between said ring means and said sealing means, and means for limiting movement of said pressure-transmitting means to a direction radial to said sealing-means, said ring means including means spaced around the circumferential extent of said ring means for applying inwardly directed pressure to said pressure-transmitting means effective to compress said sealing means in predetermined zones along the path of rotation of said ring means; said housing means including means cooperating with said ring means and arranged for moving said closure means out of closing relation with said valve member in said predetermined zones.

8. An exhaust head assembly comprising housing means and closure means defining an evacuable chamber, said closure means having an opening therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing means including at least one exhaust outlet for evacu-' ating said chamber, a stationary valve member mounted in said chamber and arranged for closing said opening in saidclosuremeans, and ex-' tensible bellows means disposed in said chamberand encircling said valve member, one end oi said bellows means being secured to said closure means around said-opening; the other end of said bellows means being secured to said housof incompressible elements ing means around said exhaust outlet, said closure means comprising resilient sealing means having said opening extending therethrough, ring means encircling said sealing means and rotatable about said sealing means, a plurality disposed between said ring means and said sealing means in spaced apart relation around said sealing means, and confining means arranged for limiting movement of said incompressible elements to a direction radial to said sealing means, the inner face of said ring means having a sinuous configuration arranged to exert pressure on said incompressible elements in spaced apart predetermined zones along the path of rotation of said ring means whereby said sealing means is alternately compressed and released during rotation of said ring means, said housing means including means cooperating with said ring means and arranged to move said closure means out of closing relation with said valve member in said predetermined zones.

9. An exhaust head assembly comprising housing means and closure means defining an evacuable chamber, said closure means having an opening therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing means including at least one exhaust outlet for evacuating said chamber, a stationary valve member mounted in said chamber and arranged for closing said opening in said closure means, and extensible bellows means disposed in said chamber and encircling said valve member, one end of said bellows means being secured to said closure means around said opening, the other end of said bellows means being secured to said housing means around said exhaust outlet, said closure means comprising resilient sealing means having said opening extending therethrough, ring means encircling said sealing means and rotatable about said sealing means, a plurality of incompressible elements disposed between said ring means and said sealing means in spaced apart relation around said sealing means, and confining means arranged for limiting movem nt of said elements to a direction radial to said sealing means, the inner face of said ring means having a sinuous configuration and being arranged to exert inwardly directed pressure on said elements in spaced apart predetermined zones along the path or rotation of said ring means efiective to compress said sealing means, said closure means including roller means associated with said ring means for movement therewith, said roller means being arranged for rolling on a circumferential portion of said housing means, generally parallel to the plane of said ring means, said circumferential portion including raised zones in generally radial alignment with said incompressible elements, said roller means and said raised zones being efiective to raise said closure means out of closing relation with said valve member during compression of said sealing means.

10. An exhaust head assembly comprising a housing having an open end, closure means for said open end of said housing, said housing and said closure means defining an evacuable chamber, said closure means having an opening therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing including at least one exhaust outlet for evacuating said chamber, a stationary valve member mounted on said housing in said chamber and being arranged for closing said opening in said closure means, and extensible bellows means disposed in said chamber and encircling said valve member, one end of said bellows means being secured to said closure means around said opening, the other end of said bellows means being secured to said housing around said exhaust; outlet, said closure means comprising a plate member journalled in said housing, a second plate member rigidly secured to said first-named plate member in generally parallel spaced-apart relation, resilient sealing means sandwiched between said plate member, said opening in said closure means extending through said plate members and said sealing means, and adjustable means for alternately compressing and releasing said sealing means, said housing including means cooperating with said adjustable means and arranged for moving said closure means out of closing relation with said valve member during compression of said sealing means, said closure means being movable into closing relation with said valve member when said sealing means is uncompressed.

11. An exhaust head assembly comprising a housing having an open end, closure means for said open end of said housing, said housing and said closure means defining an evacuable chamber, said closure m ans having an opening therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing including at least one exhaust outlet for evacuating said chamber, a stationary valve member mounted on said housing in said chamber and being arranged for closing said opening in said closure means, and extensible bellows means disposed in said chamber and encircling said valve member, one end of said bellows means being secured to said closure means around said opening, the other end 01' said bellows means being secured to said housing around said exhaust outlet, said closure means comprising a plate member journalled in said housing, a second plate member rigidly secured to said first-named plate member in generally parallel spaced-apart relation thereto, resilient sealing means sandwiched between said plate members, said opening in said closure means extending through said plate member and said sealing means, and adjustable means encircling said sealing means and rotatable about said sealing means, said adjustable means including means for alternately compressing and releasing said sealing means in response to rotation 01' said adjustable means, said housing means including means arranged in cooperating relation with said adjustable means and being constructed for moving said closure means out 01' closing relation with said valve member, said means for moving said closure means being constructed and arranged for moving said closure means in response to rotation of said adjustable means in the zones along the path of rotation wherein said adjustable means compresses said sealing means.

12. An exhaust head assembly comprising a housing having an open end, closure means for said open end of said housing, said housing and said closure means defining an evacuable cham ber, said closure means having an opening therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing including at least one exhaust outlet for evacuating said chamber,

.resilient sealing :means extending through said and said sealing 'means, ring ,housing'in said chamber and being arranged for closing said opening in said closure means, and extensible bellows means disposed in said chamber and encircling said valve member, one end of said bellows means being secured to said closure means around said opening, the other end of said bellows meansbeing secured to said housing around said exhaust outlet, said closure "means comprising a plate member journalled in said housing, a second plate member rigidly secured to said first-named plate member in generally parallel spaced-apart relation therewith, means sandwiched between said in said closure plate members means encircling about said sealplate members, said opening said sealing means and rotatable ing means, and means actuated by said ring .means for compressing said sealing means in ipredetermined zones along the path of rotation of said ring means, said ring means including means in rolling contact with the open end of said housing, said end of said housing having raised portions in radial alignment with said pre determined zones along the path of rotation of said ring means, said raised portions being effective to raise said closure means out of closing relation with said valve member in said predetermined zones along the path of rotation of said ring means.

13. An exhaust head assembly comprising a housing having an open end, closure means for said open end of said housing, said housing and said closure means defining an evacuable chamber, said closure means having an opening therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing including at least one exhaust outlet for evacuating said chamber, a stationary valve member mounted on said housing in said chamber and being arranged for closing said opening in said closure means, and extensible bellows means disposed in said chamber and encircling said valve member, one end of said bellows means being secured to said closure means around said opening, the other end of said bellows means being secured to said housing around said exhaust outlet, said closure means comprising a plate member journalled in said housing adjacent the open end of said hous ing, a second plate member rigidly secured to said first-named plate member in generally parallel spaced-apart relation thereto, resilient sealing means sandwiched between said plate members, said opening in said closure means extending through said plate members and sealing means, ring means encircling said sealing means and rotatable about said sealing means, pressure-transmitting means positioned between said ring means and said sealing means, and confining means for limiting movements of said pressure-transmitting means to a direction radial to said sealing means, said ring means including means for applying inwardly directed pressure to said pressure-transmitting means effective to compress said sealing means, in prede termined zones along the path of rotation of said ring means, said housing including means cooperating with said ring means and being or" ranged for moving said closure means out of closing relation with said valve member in said predetermined zones.

14. An exhaust head assembly comprising a housing having an open end, closure means for a stationary valve member said open end ofsaid housing, said housing and said closure means defining an evacuable chamber, saidclosure means having an opening'therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing including at least one exhaust outlet for evacuating said chamber, mounted on said housing in said chamber and being arranged for closing said opening in said closure means, and extensible bellows means disposed in said chamber and encircling said valve member, oneend of beilows means being secured to said closure means around said opening, the other end of said bellows means being secured to said housing around said exhaust outlet, said closure means comprising a plate member journalled in said housing adjacent the open end of said housing, a second plate member rigidly secured to said first-named plate member in generally parallel spaced-apart relation thereto, resilient sealing means sandwiched between said plate members, said opening in said closure meansextending through said plate members and said sealing means, ringmeans encircling said sealing means and being disposed between said plate members, said ring means being rotatable about said sealing means, and between said plate members, a plurality of incompressible elements disposed between said ring means and said sealing means and being spaced around said sealing means, and confining means for limiting movement of said incompressible elements to a direction radial to said ring means, the inner face of said ring means having a sinuous configuration efiective to press said incompressible elements inwardly against said sealing means in spaced apart predetermined zones along the path of rotation of said ring means, said ring means including means extending into rolling contact with the rim forming the open end of said housing, said rim having raised portions correlated with said predetermined zones and effective to raise said closure means out of closing relation with said valve member in response to rotation of said ring means into said predetermined zones along the path of rotation of said ring means, the remaining portions of said rim being ineffective to raise said closure means out of closing relation with said valve member.

15. An exhaust head assembly comprising housing means and closure means defining an evacuable chamber, said closure means having an opening therethrough communicating with said chamber and being adapted to receive the neck of an article to be evacuated, said housing means including an exhaust outlet for evacuating said chamber, a stationary rod-like valve member projecting inwardly from said housing means into closing relation with said opening in said closure means, said valve member having at least one fluid conduit extending longitudinally through said valve member for delivering back fill fluid to said opening, said housing means including a second conduit communicating with said first-named conduit and arranged for connection with a reservoir of back filling fluid, valve means in said second conduit for controlling flow of back fill fluid, extensible bellows means in said chamber and encircling said valve member, one end of said bellows means being secured to said closure means around said opening, the other end of said bellows means around said exhaust outlet, said closure means comprising resilient sealing means having said opening extending therethrough, and adjustable means for alternately compressing and releasing said sea1- ing means, and means cooperating with said adjustable means and arranged for moving said closure means out of closing relation with said valve member during compression of said sealing means, said closure means being free to move into closing relation with said valve member when said adjustable means is positioned so that said sealing means is uncompressed.

16. An exhaust head assembly formed by a combined port and valve assembly comprising housing means, closure means for said housing means, said closure means including resilient sealing means having a port opening adapted to receive a neck portion of an article to be evacuated, exhaust outlet means for evacuating said housing, valve means in said housing adapted to close said port opening, and mechanically actuated means arranged in mechanically cooperating relation with said sealing means and said valve means and being operable to simultaneously compress said sealing means and open said port opening during a portion of the operating cycle of said assembly and to simultaneously decompress said sealing means and close said port opening during another portion of the operating cycle of said assembly.

17. An exhaust head assembly comprising housing means and closure means defining an evacuable chamber, said closure means including resilient sealing means having a port opening therethrough communicating with said chamber and adapted to receive the neck of an article to be evacuated, exhaust outlet means for evacuating said chamber, ring means encircling said resilient sealing means and arranged for rotation around said sealing means, a plurality of balls disposed between said ring means and said sealing means for compressing said sealing means, a plurality of recessed ball seats at spaced intervals in said ring means for receiving said balls and thereby decompressing said sealing means at predetermined zones along the path oi. rotation of said ring means, and means arranged to coact with said ring means for closing said port opening in said zones wherein said balls are seated in said ball seats and for opening said port opening in the remaining zones in which said balls compress said sealing means.

References Cited in the file of this patent UNITED STATES PATENTS Number 

